In addition to the 16 wave form samplers in the Geos 3 radar altimeter there exist integrating samplers located at approximately 0.3¿ and 1¿ angles of incidence, i.e., the plateau and attitude/specular gates, respectively. For very low surface wind speed conditions where the joint probability density function for the slopes of the surface roughness is very peaked these two gates can be used to infer the form of the density. For two instances where this condition was observed, it was found that the Geos 3 altimeter data implied that the joint slope density was closer to a Laplacian form than a Gaussian form. These experimental results indicate that under conditions of very low surface wind speed the slopes of the surface roughness may depart rather markedly from the universally assumed Gaussian form. Such departures may be due to the possible trochoidal nature of small-amplitude gravity waves.